On Fri, 2025-03-14 at 05:05 +0800, Kemeng Shi wrote: > Hi All, > This series contains some cleanups and improvements which are made > during learning swapfile. Here is a summary of the changes: Nice work. > 1. Function nameing improvments. > -Use "put" instead of "free" to name functions which only do actual free > when count drops to zero. > -Use "entry" to name function only frees one swap slot. Use "entries" to > name function could may free multi swap slots within one cluster. Use > "_nr" suffix to name function which could free multi swap slots spanning > cross multi clusters. Will be nice to add some comments in the code about functions with _nr crossing the cluster boundaries and those without stay within a cluster. > 2. Eliminate the need to set swap slot to intermediate SWAP_HAS_CACHE > value before do actual free by using swap_entry_range_free() > 3. Add helpers swap_entries_put_map() and swap_entries_put_cache() as a > general-purpose routine to free swap entries within a single cluster > which will try batch-remove first and fallback to put eatch entry > indvidually with cluster lock acquired/released only once. By using > these helpers, we could remove repeated code, levarage batch-remove in > more cases and aoivd to acquire/release cluster lock for each single > swap entry. Wonder if the batching shows up in any swap performance improvement? Tim > > Kemeng Shi (9): > mm: swap: rename __swap_[entry/entries]_free[_locked] to > swap_[entry/entries]_put[_locked] > mm: swap: factor out the actual swap entry freeing logic to new helper > mm: swap: use __swap_entry_free() to free swap entry in > swap_entry_put_locked() > mm: swap: remove unneeded VM_BUG_ON(*map != SWAP_HAS_CACHE) in > swap_entry_range_free() > mm: swap: use swap_entries_free() drop last 1 flag in > swap_entries_put_nr() > mm: swap: drop last SWAP_MAP_SHMEM flag in batch in > swap_entries_put_nr() > mm: swap: free each cluster individually in swap_entries_put_map_nr() > mm: swap: factor out helper to drop cache of entries within a single > cluster > mm: swap: replace cluster_swap_free_nr() with > swap_entries_put_[map/cache]() > > mm/swapfile.c | 173 +++++++++++++++++++++++++------------------------- > 1 file changed, 86 insertions(+), 87 deletions(-) >
